Compared with the production of ordinary graphite materials, the production process of high-purity graphite has the following characteristics:
(1) Choose petroleum coke or pitch coke with as low ash content as possible, and the particle size of calcined coke mill powder needs to be particularly fine when producing fine-structure high-purity graphite;
(2) The kneaded paste needs to be processed several times by the sheeting process to make the binding agent and coke powder more effectively combined. After the paste is rolled into a sheet, it is secondly ground for forming;
(3) Compression molding is generally used (cold molding or warm molding);
(4) Need to go through 2-4 times of immersion and one or two roasting cycles;
(5) Adopting aeration graphitization purification process, inject chlorine or freon gas at a high temperature of 2000-2800℃, so that impurity elements form chlorides or fluorides to volatilize and escape, and send pure nitrogen when the furnace temperature drops to 1800℃ , So that the excess chlorine or fluorine gas is discharged to achieve the purpose of purification.
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